Crutch



CRUTCH.

APPLICATION FILED MAR- H, 1916.

Patented Augi15, 1916.

Invenror. George Hipwooc! WWWK W A'Hy 5.

GEORGE I-IIPWOOD, OF BOSTON, MASSACHUSETTS.

CRUTGH.

Application filed March 11, 1916.

To all whom it may concewt:

Be it known that I, GEORGE Hirwooo, a citizen of the United States, residing at Boston, county of Suffolk, State of Massachusetts, have invented an Improvement in Crutches, of which the following description, in connection with the accompanying drawing, is a specification, like characters on the drawing representing like parts.

This invention relates to crutches and has for one of its objects to provide a novel crutch in which the arm rest is connected to the body of the crutch through a liquid medium, thereby providing ayielding connecti on between these parts, and otherwise to improve crutches, all as will be more fully hereinafter set forth. v

In the drawings, Figure 1 is a side view of a crutch embodying my invention; Fig. 2 is an enlarged vertical section through the head of a crutch; Fig. 3 is a section on the line 33, Fig. 2.

1 indicates the crutch body which is herein shown as comprising the two sides or bows '2 which come together at their lower end, as at 8, and between which the usual handle 4 is secured.

5 is the arm rest. In the present invention the arm rest is connected to a plunger which operates in a liquid-containing cylinder, thus providing a yielding connection between the crutch body and the arm rest. At the upper end of the crutch body is a head or yoke 6 that is provided with sockets 7 in which the upper ends of the sides 2 are received, said sockets preferably being split, as shown at 8, so that they are slightly resilient and can be applied to bows of different sizes. The yoke 6 is provided with two communicating liquid-containing compartments 9 and 10, the compartment 9 being in the form of a. cylinder, and the compartment 10 being shown as surrounding the compartment 9.

11 is a plunger or piston operating in the cylinder 9 and to which the arm rest 5 is secured, said plunger having a stem 12 which extends up through the top of the yoke 6 and to the upper end of which the arm rest is secured. The communication between the cylinder 9 and the compartment 10 is at the lower end of the cylinder and a controlling device is employed at this point which controls the flow of the liquid from one compartment to the other. Said controlling device will preferably be soconstructed as to permit Specification of Letters Patent.

Patented Aug. 15, 1916.

Serial No. 83,648.

the liquid to flow more freely in one direction than in the other. In the illustrated embodiment of my invention, the controlling device is constructed to permit the liquid to flow less freely when the plunger is moving downwardly in the cylinder 9 than when it is moving upwardly. This controlling de vice is herein shown as in the form of a valve member 13 which is pivoted to the cylinder 9 at 1 1, and when closed is adapted to rest on a valve seat 15. The valve is provided with a port 16 which is constantly open. When the plunger moves downwardly, the valve is closed and the liquid is transferred from the cylinder to the chamber 10 through the port 16 only, and hence the speed of downward movement of the plunger is limited by the size of the port 16. When the plunger moves upwardly, the valve will open and allow the liquid to freely return to the cylinder and the plunger can thus have a rapid upward movement. 17 is a spring which normally resists the downward movement of the plunger, said spring operating to return the plunger into its elevated position when the weight is removed from the arm rest. This spring may have any suitable constructiom'but I have herein shown it as a closed spiral spring, the lower end of which is secured to the stem of the plunger and the other end of which is secured to the head or yoke. For this purpose I have provided a collar 18 through which the stem 12 extends and to which the upper end of the spring is fixedly secured, said collar being fixedly secured within the upper end 39 of the cylinder 9. The stem of the plunger is shown as having a collar 19 thereon to which the lower end of the spring 17 is secured in any suitable way.

The amount of liquid in the communicat ing chambers is less than the capacity thereof and when the plunger is in its elevated position, the cylinder 9 will be filled with liquid, but the compartment or chamber 10 will be only partially filled with liquid. WVhen weight is applied to the arm rest the plunger will be forced downwardly in the cylinder and the liquid will be forced out through the port 16, the size of the port de termining the speed at which the plunger can move downwardly. The spring 17 also resists this downward movement. As the liquid is forced into the chamber 10, the air in said chamber will be compressed, thus giving added resistance to the downward movement of theplunger. The volume of liquid and air in the compartments is so proportioned that the plunger cannot reach the bottom of the cylinder under any ordinary weight which will be applied to the crutch. As soon as the weight is relieved from the arm rest, the spring will return the plunger to its elevated position and the valve 18 will open, thus permitting the liquid to freely return to the cylinder.

When the crutch is being used and the Weight of the user is applied to the arm rest, said arm rest will yield downwardly, thus providing a yielding support for the cripple which is much more comfortable than a solid unyielding support would be. As soon as the weight is relieved from the crutch for the next step, the arm rest will immediately be returned to its normal position. The crutch may be provided with a foot 21 of any suitable or usual construction.

I claim:

1. In a crutch, the combination with a crutch body, of a head secured to the upper end of the body, a liquid-containing cylinder carried by said head, a plunger operating in said cylinder, an arm rest secured to the plunger, a chamber communicating with said cylinder, a controlling device interposed between said chamber and cylinder and which controls the flow of liquid from one to the other as the plunger moves in said cylinder, said controlling device permitting the liquid to flow more freely in one direction than in the other.

2. In a crutch, the combination with a crutch body, of. a head at the upper end of the crutch body having two communicating liquid-receiving compartments, one of which is in the form of a cylinder, at plunger movable in said cylinder, an arm rest secured to the plunger, and a controlling device interposed between said compartments and which controls the flow of liquid from one to the other, said device permitting the liquid to flow more freely in one direction than in the other.

3. In a crutch, the combination with a crutch body, of a head at the upper end of the crutch body having two communicating liquid-receiving compartments, one of which is in the form of a cylinder, a plunger movable in said cylinder, an arm rest secured to the plunger, and a controlling device interposed between said compartments and which controls the flow of liquid from one to the other, said device permitting the liquid to flow more freely when the plunger is moving upward than when it is moving downv ward.

4:. In a crutch, the combination with a crutch body, of a head at the upper end of the body having two communicating liquidreceiving compartments, one of which is in the form of a cylinder, a plunger movable in said cylinder, an arm rest secured to the plunger, a spring resisting the downward movement of the plunger, and a controlling device interposed between said compartments and which controls the flow of the liquid from one compartment to the other, said controlling device permitting the liquid to flow less freely when the plunger is moving downwardly than when it is moving upwardly.

In testimony whereof I have signed my name to this specification.

GEORGE HIPWOOD.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. C. 

